Improvement in grinding axes



utcd gitanas parte een.

Letters Patent No. 93,727, dated August 17, 1869.

l IMPROVEMENT IN @BINDING Axes.-

The Schedule referred to in these Letters Patent and mal-:ing part of the same.

` in the manner of grinding as invented by me is fully shown.

Figures 2 and 3 represent appliances to aid the grinder in properly holding the 'axe to be ground; to the stone.

In grinding axes, as heretofore done, the grinder or operatolsat upon a seat that projects over the top of the stone, and the grinding was done on the top of the stone only, the effect of which was, that every two .or three hours the grinding must stop, whilethe stone was turned off or t1-ucd, it wearing into holes, depressions, or ridges, which caused great loss of time and very great wear or destruction of the-stone..

The object and purpose of my invention are'to still avail myself of grinding on top of the stone, in the usual way, and to still keep ,the stone true, not by turning it down wastefully by atool, but by the act of grinding upon it at a point dierent from, but in addition to; the grinding on the top of the stone, and where the resistance comes upon the frame or other solid structure to Such a degree as to be a gauge for rounding or tr'uing the stone, while the top grinding wears it out of true; and y My invention consists in certain devices for grinding axes at two points, at one and the same time, viz, at the top and at one ofthe ends, so that the end grinding shall keep the stone true, and wear down all the inequalities in the stone which top grinding invariably produces.

' To enable others skilled in the art t'o make and use my-invention, I will proceed to describe the same with reference to the drawings.

A represents a frame upon whicha grinding-stone,B, is mounted and revolved, in any. of the usual wellknown ways.

Upon an adjustable support, c, at one end of the frame, there is arranged a lever-seat, D, upon'which the operator sits to grind axes, in the usual well-known way.

Grinding thus,l on top of the stone, with the weight and pressure directly upon the stone, the latter, particularly in such softer placesasare always found in grindstones, wears into holes, depressions, ridges, or other irregular shapes, 'so much so, that at vshort pevthe face ofthe stone for this purpose.

riods, of two hours or so, the operator must cease grinding, and turn ff, or round, or true, as 'it is called, the stone, thus not only losing time, but wasting away his stone. i

` I avoid all this loss of time and wear, or waste of stone, by adding to the machine as follows:

At one end of the frame, and at what may be termed the front of the stone, I arrange a plate-rest, E, which can be set to or from the stone, as may be desired. I then provide a washer, or ring, (t, which may be open, as shown, and a lever, b, with a piu, c, in itsend, that will enter any of the holes l in the plate-rest E.

The axe c to be ground at thejfront of the stone is taken and clamped in a pair of suitably-prepared tongs, j, and laid upon the plate-restll. rlhen, with lthe washer, or ring, or sometimes without it, the lever b has its point, or pin c placed in one of the holes 'of the plate-rest, which is fixed `rmly to the frame, as seen in the drawing, fig. 1, and the operator, with his free hand or shoulder, or both, presses .the axe against the stone, While with the tongs with which he holds'it, he guidesthe axe so as to present its emved surface to the stone.

It will `be perceived, that by grinding at this point, and by the means used, the stone runs against what may be termed an unyielding or inelastic sur` faoe(the axe,) which, by the lever behind it, may be said to maintain aposition always uniformly distant from thecentre of the stone, so that any of the grinding-surface of the stone beyond a true circle will bear harder and Wear faster than the surfaces inside of such circle, that would touch the stone at all points; or, in other words, the proj ectingsurface of the stone doing the most work will wear fastest, while the axe, not

being suddenly jumped or forced into the depressions or soft parts of the stone, as itis by the top grinding, the whole surface is brought to a true circle, and this, too, by grinding an axe against it, and not Wearing and wasting away the stone by a tool traversing across On the top of the stone, the axe ground there bears hardest on the softer portions of the stone, while at the front the reverse is the case, as the harder or unworn portions of the stone-are most prominent, and so take harder against the axe, the sunken portions not reaching the v axe at this grinding-point. And thus the two griuding-points, one doing the hardest work at the softer parts of the stone, and the other just the reverse, viz, making the projecting (which are the harder) portions do the hardest 'of the grinding, and thus keeping the 'stone quite true and circular, and by grinding, and not turning off with a tool, which is a total waste of the stone.

I have not represented, and do not describe the shields put up to protect the grindersv from the water of ordinary-sized axes, the pin c of the lever can be placed in any of the holes d, with its shoulder resting on the plate E directly.

Having thus fully described my invention,

What I claim therein as new, and desire to secure by Letters Patent, is-

In combination with a lever-seat whereon the grinder sits, and a. stone whereby axes are ground on top, in the' usual way, a. rest, tongs, and holding-lever, at the end or front of the stone for grinding axes also, so that the irregular wear of the top grinding may be corrected by the end grinding, and the stone thus kept true, by which'time and economy of stone are both availed of, the construction and operation being substantially as described. HARVEY MANN.

Witnesses A. B. STOUGHTON, EDMUND MASSON. 

